With my starter and Webasto both working it is time for my next repair. My air compressor has been slowly dying for the last year and before my next long drive it needs to go. If you are interested in a bit of my compressors history here is a few posts:

The oil drain is just a hole in the casting that allows the oil in the compressor crankcase to drain into the engine housing. After you remove your compressor, if you'll look in the area where the drive gear is located, you'll see it.